Several years ago I got to go to Pearl Harbor and the Arizona Memorial. It was very...surreal. I don't know if it does it anymore, but at the time you could still see ripples of oil surfacing every couple minutes. And people had tossed several leis into the water, and on the gun turrets. You can actually see some of the boat from the surface. It was amazing to actually see something from my history book in person.

We also went to the Bowfin, which is a submarine that was right next to the Memorial. That was pretty cool, too. I don't remember if we rented the hand-held tour guide thingies, but I couldn't believe how cramped it was.
Besides the usual ceremonies they have every year, including a moment of silence at 7:55am (the time of the first attack) they usually have services for Pearl Harbor survivors who died during the year who wished to be buried with their shipmates. They get piped aboard for the last time and then divers lay their ashes within the ships.